Normalize each video in the playlist separately with FFmpeg’s loudnorm filter. For offline files, analyze each file first, then process it using that file’s measurements and the same chosen integrated-loudness, loudness-range and true-peak targets. This makes the workflow repeatable without treating unrelated videos as one audio program. There is no single universal YouTube upload target established by the official sources cited here, so choose targets for your material and delivery needs—not because a particular LUFS value is supposedly a YouTube requirement.
What loudness normalization changes—and what it does not
Perceived volume across a playlist depends on more than a file’s peak level. FFmpeg’s loudnorm implements EBU R128 loudness normalization and provides controls for three related measurements:
- Integrated loudness (
I): an estimate of the program’s overall perceived level, expressed in LUFS. - Loudness range (
LRA): a measure of how loudness varies over time, expressed in LU. - Maximum true peak (
TP): a ceiling for peaks, including inter-sample peaks, expressed in dBTP.
These targets do different jobs. Matching integrated loudness can help separate videos feel more consistent overall; it does not make every moment equally loud. LRA concerns variation within a program, while TP limits peaks. Set them as a coordinated group, and listen to the result—especially when a playlist mixes gameplay, commentary, music, or cinematic clips.
FFmpeg documents loudnorm as supporting dynamic and linear modes, plus single-pass operation for files and livestreams and double-pass operation for files. See the FFmpeg Filters Documentation, in the loudnorm section.
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Choose targets for the project, not an alleged YouTube standard
The FFmpeg documentation lists defaults of I=-24.0, LRA=7.0, and TP=-2.0. These are filter defaults, not a YouTube creator upload specification. FFmpeg documents valid parameter ranges of -70 to -5 LUFS for I, 1 to 50 LU for LRA, and -9 to 0 dBTP for TP.
The commands below use I=-16, LRA=11, and TP=-1.5 only as illustrative settings. They are not required by YouTube, and no cited official source establishes them as ideal for every game, voice track, or music bed. Pick targets that suit your delivery brief and material, then use the same targets for each playlist entry.
Normalize each video with a two-pass workflow
For an offline batch, two passes let you measure each actual input before processing it. Keep the measurements tied to their source file: do not analyze a concatenation of unrelated uploads and use that as the measurement set for every video.
1. Analyze one input file
Run an analysis pass for each video, replacing the filename and, if needed, the illustrative targets:
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ffmpeg -i input.mp4 -af "loudnorm=I=-16:LRA=11:TP=-1.5:print_format=json" -f null -FFmpeg prints a JSON measurement block. Save that file’s reported integrated loudness, loudness range, true peak, threshold, and offset. Repeat the analysis for each playlist video; do not reuse one file’s measurements for another.
2. Process the same file using its own measurements
Substitute the exact measured values from that input’s analysis in place of the ellipses below. Keep the targets identical to the analysis pass. The example maps the first audio stream and copies video without re-encoding it:
ffmpeg -i input.mp4 -map 0:v? -map 0:a:0 -af "loudnorm=I=-16:LRA=11:TP=-1.5:measured_I=...:measured_LRA=...:measured_TP=...:measured_thresh=...:offset=...:linear=true:print_format=summary" -c:v copy output.mp4The ellipses are instructions to replace them, not literal filter values. The source’s audio is filtered, so it must be encoded; FFmpeg will select an audio encoder unless one is specified. Choose an audio codec and bitrate appropriate to the output format and delivery needs rather than assuming the input audio can be copied through a filter.
-map 0:v? selects video streams if present, and -map 0:a:0 selects the first audio stream. If the intended commentary or game mix is not the first audio stream, map the correct stream instead. Check stream mapping, channel layout, subtitles, and any other streams you need to retain. The sample does not preserve every possible stream, and copying streams blindly may not suit a particular container.
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3. Repeat independently and inspect the result
Run both passes separately for every playlist video. In the second-pass summary, inspect the reported normalization type. With linear=true, FFmpeg can fall back to dynamic normalization when the requested LRA is below the source LRA or the gain needed would exceed the true-peak ceiling.
One-pass or two-pass; linear or dynamic?
| Choice | What it does | When it may fit |
|---|---|---|
| One-pass | Normalizes without the explicit first-pass measurements used by the two-pass workflow. FFmpeg documents it for files and livestreams. | When a simpler workflow or live operation matters more than using per-file measurements from an analysis pass. |
| Two-pass | Uses measurements from the actual input file to guide its processing pass. | For offline playlist batches where you want a repeatable target set applied per video. |
| Linear mode | Applies constant gain, preserving source dynamics if the constraints can be met. It requires measured values. | When preserving the source’s dynamic shape is important and the requested loudness and peak limits permit it. |
| Dynamic mode | Can reshape level over time to meet targets when simple linear scaling cannot. FFmpeg documents true-peak detection in dynamic mode as upsampling to 192 kHz. | When a fixed gain cannot satisfy the targets; audition quiet passages and deliberately dynamic material. |
Linear mode is not guaranteed just because linear=true is specified. The filter’s fallback to dynamic mode is important if preserving dynamics is a priority. Conversely, dynamic processing is not simply a fixed volume adjustment, so listen for whether it changes the intended contrast between quiet and loud moments.
Check normalized files before uploading
- Measure the encoded output with FFmpeg’s EBU R128 measurement capability or inspect the
loudnormsummary. - Confirm that the output’s integrated loudness and true peak fall within the project tolerances you chose.
- Listen to loud and quiet sections, including dialogue, explosions, menus, and music where applicable.
- Play the end of one video into the beginning of the next. Matching measurements do not guarantee that two different mixes will sound equally loud to every listener.
- Verify that the expected audio stream and channel layout made it into the output.
Account for YouTube’s playback processing
The rendered file is only one stage in what a viewer hears. YouTube Help says Stable volume is on by default when watching videos and can balance the range between quiet and loud parts. It is not available for every video and is turned off for YouTube Music and official music videos; viewers can toggle it in the player. YouTube also describes automatic audio-level and mixing adjustments, Stable volume, Voice boost, and channel controls for future uploads. Those settings do not affect ads or videos already uploaded. Details are in YouTube’s Control video volume on your device – Computer and Video & audio quality enhancements help pages.
Source normalization can improve consistency before upload, but it cannot guarantee identical playback for every viewer: YouTube enhancements and individual playback settings may intervene. A particular LUFS target does not disable Stable volume or guarantee uniform playback.
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Troubleshooting common problems
The second pass reports dynamic normalization
Check the reported normalization type and the measured source LRA. FFmpeg may switch from linear mode if the requested target LRA is lower than the source LRA or if linear gain would violate the TP ceiling. Accept dynamic processing if it sounds right, or revisit the project targets; do not assume the filter honored linear mode merely because it was requested.
The playlist still sounds uneven
Confirm that every video was measured and processed independently with the same targets. Then audition transitions and representative quiet and loud sections. Similar integrated loudness does not make different content, mixes, or dynamics perceptually identical.
The wrong sound is normalized, or audio is missing
Inspect the input’s streams and revise -map 0:a:0 if the intended audio is not the first audio stream. If a source has multiple audio tracks, select the one viewers should hear; confirm the output retains it and has the expected channel layout.
The output does not preserve all the source tracks
The illustrative mapping selects video and one audio stream; it does not preserve every subtitle, data, or alternate audio stream automatically. Add explicit mappings for streams you need, and check that the selected streams and codecs are compatible with the output container.
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The encoded output measures differently from the target
Inspect the second-pass summary and measure the encoded output, not just the pre-encode input. Confirm the measured values were copied accurately, that the same targets were used in both passes, and that the chosen output encoding is suitable. Make decisions against your project tolerances rather than treating an illustrative target as a platform rule.
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